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Thread: Adding extension psu cables makes the performance of a PSU worse?

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    Default Adding extension psu cables makes the performance of a PSU worse?

    I'm talking about not replacing the whole cable but just adding the extension between the original cable and the 24 pin, 8 pin plug etc.

    I have a Prime Snow SIlent 750 and i was planning to buy those Silverstone white extension cables, will it make any difference in terms of performance, like ripple suppresion and all that weird stuff?

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    Yes, of course.

    Adding wires adds resistance. Added resistance lowers voltage. Lowering voltage requires increase in current.

    Extension cables don't come with sense wires either, so the PSU can't detect the drop and compensate either.

    It's a cascading shit storm.

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    To add to this discussion I was wondering what gauge of power cord would be preferred for a psu? I am looking to buy a replacement left-angle cable as my pc is on my desk and have limited desk space and the cord getting in the way of the mouse. Looking at this one:

    https://www.amazon.com/gp/product/B0...KIKX0DER&psc=1

    This is a 14 AWG cable. Tripp-lite a company that has been recommended a lot on this forum also sells one but its only 18 AWG.

    Thanks
    Last edited by davidm71; 10-01-2018 at 02:13 PM. Reason: Tripped

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    Depends on the power; 18 AWG is good up to 10 amp, 14 gauge is good for 15 amp

    Gauge 14 is about 60% thicker than gauge 14, so can take 60% more current (heating goes like I^2 R, resistance goes inversely as cross-sectional area which goes like diameter^2)

    My guess is that your PC is below 1 KW so either should be fine
    Last edited by ashiekh; 10-01-2018 at 05:17 PM.

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    Quote Originally Posted by jonnyGURU View Post
    It's a cascading shit storm.
    Actually I've wondered about that; if a power station sags under load and the connected devices respond by pulling more current it could bring the station down.

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    yes bc it adds up resistance

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    Quote Originally Posted by COFASA View Post
    yes bc it adds up resistance
    I think the issue is that the power supply will reduce its resistance in response to a voltage drop
    Last edited by ashiekh; 10-02-2018 at 03:16 PM.

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    @up

    Extension cables don't come with sense wires either, so the PSU can't detect the drop and compensate either.

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    Default 1KW and above?

    Quote Originally Posted by ashiekh View Post
    Depends on the power; 18 AWG is good up to 10 amp, 14 gauge is good for 15 amp

    Gauge 14 is about 60% thicker than gauge 14, so can take 60% more current (heating goes like I^2 R, resistance goes inversely as cross-sectional area which goes like diameter^2)

    My guess is that your PC is below 1 KW so either should be fine
    So 14 or 16 AWG for 1KW and 1200W PSUs?

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    16 AWG is good for 13 A, so in theory good enough.
    Last edited by ashiekh; 10-02-2018 at 03:17 PM.

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